syzbot


KASAN: use-after-free Read in ntfs_attr_find (2)

Status: upstream: reported C repro on 2023/03/01 23:29
Labels: ntfs (incorrect?)
Reported-by: syzbot+ef50f8eb00b54feb7ba2@syzkaller.appspotmail.com
First crash: 100d, last: 11d

Cause bisection: failed (error log, bisect log)
Discussions (4)
Title Replies (including bot) Last reply
[syzbot] Monthly ntfs report (Jun 2023) 0 (1) 2023/06/02 08:40
[syzbot] Monthly ntfs report (May 2023) 0 (1) 2023/05/02 07:18
[syzbot] Monthly ntfs report 0 (1) 2023/03/31 15:00
[syzbot] [ntfs?] KASAN: use-after-free Read in ntfs_attr_find (2) 0 (1) 2023/03/01 23:29
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in ntfs_attr_find ntfs C done 74 118d 285d 24/24 fixed on 2023/02/24 13:50
linux-6.1 KASAN: use-after-free Read in ntfs_attr_find 3 44d 55d 0/3 upstream: reported on 2023/04/12 03:04
linux-4.14 KASAN: slab-out-of-bounds Read in ntfs_attr_find (2) C 31 99d 285d 0/1 upstream: reported C repro on 2022/08/25 11:21
linux-4.19 KASAN: use-after-free Read in ntfs_attr_find (2) C 1 100d 100d 0/1 upstream: reported C repro on 2023/02/26 02:15
linux-4.14 KASAN: use-after-free Read in ntfs_attr_find C done 4 967d 986d 1/1 fixed on 2020/11/12 10:36
linux-4.19 KASAN: use-after-free Read in ntfs_attr_find C done 13 951d 982d 1/1 fixed on 2020/11/27 11:32
linux-5.15 KASAN: slab-out-of-bounds Read in ntfs_attr_find 1 43d 43d 0/3 upstream: reported on 2023/04/24 04:27

Sample crash report:
loop0: rw=0, sector=32768, nr_sectors = 2 limit=4096
syz-executor466: attempt to access beyond end of device
loop0: rw=0, sector=32770, nr_sectors = 2 limit=4096
==================================================================
BUG: KASAN: use-after-free in ntfs_attr_find+0xa5e/0xba0 fs/ntfs/attrib.c:609
Read of size 2 at addr ffff88807394b152 by task syz-executor466/5001

CPU: 1 PID: 5001 Comm: syz-executor466 Not tainted 6.4.0-rc2-syzkaller-00338-ge2065b8c1b01 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
 print_report mm/kasan/report.c:462 [inline]
 kasan_report+0x11c/0x130 mm/kasan/report.c:572
 ntfs_attr_find+0xa5e/0xba0 fs/ntfs/attrib.c:609
 ntfs_attr_lookup+0x105a/0x2070 fs/ntfs/attrib.c:1213
 ntfs_read_locked_attr_inode fs/ntfs/inode.c:1239 [inline]
 ntfs_attr_iget+0x656/0x26f0 fs/ntfs/inode.c:238
 load_system_files fs/ntfs/super.c:1808 [inline]
 ntfs_fill_super+0x28ab/0x93f0 fs/ntfs/super.c:2900
 mount_bdev+0x357/0x420 fs/super.c:1380
 legacy_get_tree+0x109/0x220 fs/fs_context.c:610
 vfs_get_tree+0x8d/0x350 fs/super.c:1510
 do_new_mount fs/namespace.c:3039 [inline]
 path_mount+0x134b/0x1e40 fs/namespace.c:3369
 do_mount fs/namespace.c:3382 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount fs/namespace.c:3568 [inline]
 __x64_sys_mount+0x283/0x300 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd7c9d9c5da
Code: 48 c7 c2 c0 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 a8 00 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe7f085bd8 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fd7c9d9c5da
RDX: 000000002001f6c0 RSI: 000000002001f640 RDI: 00007ffe7f085be0
RBP: 00007ffe7f085be0 R08: 00007ffe7f085c20 R09: 0000000000000000
R10: 0000000000008703 R11: 0000000000000286 R12: 0000000000000004
R13: 00005555565292c0 R14: 00007ffe7f085c20 R15: 0000000000000000
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001ce52c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x7394b
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 ffffea0001ce5308 ffffea0001ce2648 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 5001, tgid 5001 (syz-executor466), ts 40333644051, free_ts 40344094319
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3502
 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768
 __folio_alloc+0x16/0x40 mm/page_alloc.c:4800
 vma_alloc_folio+0x155/0x890 mm/mempolicy.c:2240
 do_anonymous_page mm/memory.c:4085 [inline]
 do_pte_missing mm/memory.c:3645 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault+0x224c/0x41c0 mm/memory.c:5089
 handle_mm_fault+0x2af/0x9f0 mm/memory.c:5243
 do_user_addr_fault+0x2ca/0x1210 arch/x86/mm/fault.c:1349
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1302 [inline]
 free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2564
 free_unref_page_list+0xe3/0xa70 mm/page_alloc.c:2705
 release_pages+0xcd8/0x1380 mm/swap.c:1042
 tlb_batch_pages_flush+0xa8/0x1a0 mm/mmu_gather.c:97
 tlb_flush_mmu_free mm/mmu_gather.c:292 [inline]
 tlb_flush_mmu mm/mmu_gather.c:299 [inline]
 tlb_finish_mmu+0x14b/0x7e0 mm/mmu_gather.c:391
 unmap_region+0x23d/0x2d0 mm/mmap.c:2222
 do_vmi_align_munmap+0xe26/0x1580 mm/mmap.c:2473
 do_vmi_munmap+0x26e/0x2c0 mm/mmap.c:2530
 __vm_munmap+0x133/0x3b0 mm/mmap.c:2805
 __do_sys_munmap mm/mmap.c:2830 [inline]
 __se_sys_munmap mm/mmap.c:2827 [inline]
 __x64_sys_munmap+0x62/0x80 mm/mmap.c:2827
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff88807394b000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88807394b080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88807394b100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                 ^
 ffff88807394b180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88807394b200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Manager Title
2023/05/22 07:47 upstream e2065b8c1b01 4bce1a3e .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-kasan-gce-root KASAN: use-after-free Read in ntfs_attr_find
2023/02/25 23:27 upstream 489fa31ea873 ee50e71c .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
2023/02/25 23:20 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 2ebd1fbb946d ee50e71c .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci-upstream-gce-arm64 KASAN: use-after-free Read in ntfs_attr_find
2023/05/25 20:34 upstream 933174ae28ba 0513b3e6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
2023/05/05 08:21 upstream 78b421b6a7c6 518a39a6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
2023/04/20 19:43 upstream cb0856346a60 a219f34e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
2023/04/03 15:40 upstream 7e364e56293b 41147e3e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
2023/03/24 13:33 upstream 1e760fa3596e f94b4a29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
2023/03/02 00:48 upstream ee3f96b16468 f8902b57 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: use-after-free Read in ntfs_attr_find
* Struck through repros no longer work on HEAD.